The present invention relates to a map editing-and-displaying apparatus, a map managing system, a map managing method, and a map storing medium. In particular, the invention relates to a map editing-and-displaying apparatus, a map managing system, a map managing method, and a map storing medium that are used as or for a vehicular navigation apparatus etc.
Vehicular navigation apparatuses as map editing-and-displaying apparatuses will be described below. JP-A-46379/1992 discloses a conventional vehicular navigation apparatus as a map editing-and-displaying apparatus that is equipped with means for receiving, by radio, latest map data of an area requested by a user. The navigation apparatus disclosed in this publication is to display a road map taking latest road information into consideration. A navigation apparatus aboard an automobile or the like sends out a signal for requesting a road map of an area where the automobile exists. The navigation apparatus receives and stores roadmap information that is transmitted as a radio signal, and corrects pre-stored roadmap information using the thus-received roadmap information. In this manner, a road map is always displayed on the basis of latest information.
JP-A-232433/1999 discloses an apparatus in which access states of respective map-data-acquired areas are managed and map data of areas that are used at low frequencies can be erased. A map display control system disclosed in this publication is intended to reduce the amount of data to be handled by a server and to increase an initial map display speed and a map display speed at the time of such a manipulation as movement, enlargement, and reduction. A client terminal is connected to a server having a map database via a communication channel. The server manages the map database on a data area basis and a data type basis using mesh layer index information. In response to a map data request from the client terminal, the server extracts map data from the map database and sends the extracted map data to the client terminal. On the basis of a map display request, the client terminal determines a data area and a data type of a map data request range. The client terminal sends a map data request to the server on a data area basis and a data type basis. The client terminal stores, in a storing means, map data that are transmitted from the server. The client terminal manages data areas and data types and displays a map on a display device.
However, in the conventional map editing-and-displaying apparatuses, only such information as a code indicating an area and an acquisition date and time are appended to acquired map data. A map can be identified only by using a list of such information or displaying the map actually. However, a user of a vehicular navigation apparatus may not be familiar with maps, and it is very difficult for such a user to identify a desired map from a list of maps being stored. The case that map data are acquired on an area basis is associated with another problem that it takes long time to select an area while looking at a map and it is very difficult for a person who is not familiar with maps to acquire a necessary map.